1. Field
The inventive concept relates to a backlight assembly and a display device including the same.
2. Description of the Related Art
A liquid crystal display (LCD) displays an image by altering the arrangement of the liquid crystals disposed between two glass substrates. The altering the arrangement of the liquid crystals is performed by applying different voltages to electrodes in the upper and lower glass substrates. Unlike cathode ray tubes (CRTs) and plasma display panels (PDPs), LCDs are non-self-luminous display devices. Therefore, LCDs cannot be used in places without light. To overcome this drawback and use LCDs in dark places, a backlight assembly which irradiates light uniformly to a liquid crystal display panel is required.
A backlight assembly includes a light source, a diffusion plate, and optical sheets. A light-emitting diode (LED) light source having high efficiency is widely used as the light source of the backlight assembly. In a direct-illumination type backlight assembly, an optical lens is placed on an LED light source in order to increase the diffusion of light emitted from the LED light source.
In this case, light emitted upward from the LED light source is diffused by the optical lens. However, light emitted from sides of the LED light source or emitted downward from the LED light source fails to enter the optical lens and leaks toward a lower housing. To recycle the leaked light, a reflective sheet is placed on the lower housing.
Here, the reflective sheet should not cover the optical lens. Thus, the reflective sheet includes an opening through which the optical lens can pass. Meanwhile, no reflective sheet is placed under the optical lens. Therefore, it is difficult to reflect light properly. To improve reflection efficiency, a sub reflective sheet may be placed under the optical lens. However, if the sub reflective sheet is not properly coupled to a main reflective sheet, a lifting of the main reflective sheet may occur, thereby degrading light quality.